AP Bio membrane and transport

Passive Transport

No Energy required

High-low concentration

Until equilibrium

Ex: Diffusion, Osmosis, facilitated diffusion

Active Transport

Energy is required (ATP)

Low-High gradient

Against concentration gradient

Ex: Na/K pump

Endocystosis (phagocytosis: eating &pinocytosis : drinking)

Exocytosis- waste removal

Phospholipid Bi-layer

A double layer of phospholipids that forms the basic structure of cell membranes, with hydrophilic heads facing outward and hydrophobic tails inward, providing a barrier to most water-soluble substances.

Integral protein (transport protein)

A type of membrane protein that spans the entire phospholipid bilayer and facilitates the transport of molecules across the cell membrane, either by forming channels or by acting as carriers.

Peripheral proteins

Proteins that are attached to the membrane's surface and do not penetrate the lipid bilayer. They play roles in signaling, maintaining cell shape, and connecting to the cytoskeleton.

Carbohydrates (glycolipids)

Molecules attached to lipids or proteins in the cell membrane, involved in cell recognition and communication.

Receptor proteins (glycoproteins)

Proteins embedded in the cell membrane that bind signaling molecules, triggering a cellular response. They play a key role in cell communication and signaling pathways.

Cholesterol

A type of lipid that is interspersed within the phospholipid bilayer of cell membranes, providing stability and fluidity.

Extracellular matrix

A network of proteins and carbohydrates outside the cell that provides structural support, regulates communication, and influences cell behavior.

Cytoskeleton

The cytoskeleton provides structural support to the plasma membrane, helps control its shape, and organizes membrane proteins. It is also involved in dynamic processes like cell motility, cell division, intracellular transport, and the formation of specialized membrane domains